The largest study of its kind showed that exposure to road traffic and railway noise can increase the risk of dementia.
Research has always linked traffic noise to health conditions including heart disease, diabetes and obesity, but research on traffic noise and dementia is few and small, and the results of the research are also inconsistent.
Now, an “impressive” study involving 2 million adults has been conducted for more than ten years and has concluded that people living in areas with noisy traffic face a higher risk of dementia, especially in the Alzheimer’s Silent disease. The results of the study were published on BMJ.
Researchers investigated the association between long-term residential exposure and dementia risk for 2 million people over 60 years of age living in road traffic and railroad noise. Denmark Between 2004 and 2017. Estimated the exposure levels on the most and least exposed side of the building at each residential address in the country.
After considering potential influencing factors related to residents and their communities, the study concluded that of the 8,475 cases of dementia registered in Denmark in 2017, as many as 1,216 were attributable to traffic noise.
Those ones, “It is estimated that the diagnosis of 963 patients was attributed to road traffic noise, and the diagnosis of 253 patients was attributed to railway noise.”
“In this large national cohort study, we found that traffic noise from road traffic and railways is associated with an increased risk of all-cause dementia and dementia. Subtypes, especially Alzheimer’s disease,” the researchers wrote.
They said that in general, a pattern with higher risks and higher levels of noise exposure was found. “If these findings are confirmed in future studies, they may have a significant impact on the estimated burden of disease and health care costs caused by traffic noise,” they said.
Dementia is one of the biggest health challenges in the world. Globally, by 2050, the number of people suffering from dementia is expected to exceed 130 million. In addition to recognized risk factors, such as unhealthy lifestyles, experts increasingly believe that environmental factors may play a role in the development of dementia.
Previous studies have linked air pollution to the risk of dementia, but in this study, researchers found a separate link between traffic noise and dementia.
The researchers said that the results of the study indicate that it is possible to reduce the burden of dementia by solving the traffic noise problem. They said: “Expanding our understanding of the harmful effects of noise on health is essential for setting priorities and implementing effective policies and public health strategies, with a focus on preventing and controlling diseases, including dementia.”
Possible explanations that noise may affect health include the release of stress hormones and sleep disturbances, which can lead to heart disease, changes in the immune system, and inflammation-all of which are considered to be related to the onset of dementia.
The study was observational, so the cause was not determined, and there were many limitations, such as lack of information on household sound insulation that may affect noise exposure. However, its advantages include its large scale, long follow-up time, and high-quality assessment of noise exposure.
Dr. Ivan Koychev, a dementia expert and senior clinical researcher at Oxford University who was not involved in the investigation, described it as “high-quality research.”
He added: “The author has controlled the level of traffic pollution and the results have been strengthened, and it has recently been proved to be related to dementia and other diseases.”
Professor Timothy Griffiths, Professor of Cognitive Neurology at Newcastle University, also did not participate in the study. He said it was “an impressive large-scale epidemiological study” and “evaded why noise exposure is associated with dementia. Related issues”.
Extensive exposure to noise, limited tools that can help people protect themselves, support the world healthy American researchers wrote in a related editorial in BMJ that the organization’s argument is that “noise pollution is not only an environmental nuisance, but also a threat to public health.”
They said: “Noise reduction through traffic and land use plans or building codes should be a public health priority.”
Dr. Rosa Sancho, head of research at the Alzheimer’s Research Center in the United Kingdom, said that the best way to keep your brain healthy is to keep your mind and body active, eat a healthy and balanced diet, and control your weight, cholesterol and blood pressure.
